52 lines
1.7 KiB
Diff
52 lines
1.7 KiB
Diff
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From: Thierry Reding <treding at nvidia.com>
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The Rockchip IOMMU driver unconditionally executes code and registers a
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struct iommu_ops with the platform bus irrespective of whether it runs
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on a Rockchip SoC or not. This causes problems in multi-platform kernels
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where drivers for other SoCs will no longer be able to register their
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own struct iommu_ops or even try to use a struct iommu_ops for an IOMMU
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that obviously isn't there.
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The smallest fix I could think of is to check for the existence of any
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Rockchip IOMMU devices in the device tree and skip initialization
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otherwise.
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This fixes a problem on Tegra20 where the DRM driver will try to use the
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obviously non-existent Rockchip IOMMU.
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Reported-by: Nicolas Chauvet <kwizart at gmail.com>
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Cc: Heiko Stuebner <heiko at sntech.de>
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Cc: Daniel Kurtz <djkurtz at chromium.org>
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Reviewed-by: Heiko Stuebner <heiko at sntech.de>
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Tested-by: Heiko Stuebner <heiko at sntech.de>
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Signed-off-by: Thierry Reding <treding at nvidia.com>
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---
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Changes in v2:
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- do not fix up module exit function since it's dead code
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- drop reference to struct device_node
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drivers/iommu/rockchip-iommu.c | 7 +++++++
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1 file changed, 7 insertions(+)
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diff --git a/drivers/iommu/rockchip-iommu.c b/drivers/iommu/rockchip-iommu.c
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index 6a8b1ec4a48a..9f74fddcd304 100644
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--- a/drivers/iommu/rockchip-iommu.c
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+++ b/drivers/iommu/rockchip-iommu.c
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@@ -1015,8 +1015,15 @@ static struct platform_driver rk_iommu_driver = {
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static int __init rk_iommu_init(void)
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{
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+ struct device_node *np;
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int ret;
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+ np = of_find_matching_node(NULL, rk_iommu_dt_ids);
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+ if (!np)
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+ return 0;
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+
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+ of_node_put(np);
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+
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ret = bus_set_iommu(&platform_bus_type, &rk_iommu_ops);
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if (ret)
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return ret;
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--
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2.1.3
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